"""
题目：利用ellipse 和 rectangle 画图。。　
"""
from tkinter import Canvas, mainloop

if __name__ == '__main__':
	canvas = Canvas(width=400, height=600, bg='white')
	left = 20
	right = 50
	top = 50
	num = 15
	for i in range(num):
		canvas.create_oval(250 - right, 250 - left, 250 + right, 250 + left)
		canvas.create_oval(250 - 20, 250 - top, 250 + 20, 250 + top)
		canvas.create_rectangle(20 - 2 * i, 20 - 2 * i, 10 * (i + 2), 10 * (i + 2))
		right += 5
		left += 5
		top += 10
	
	canvas.pack()
	mainloop()
